The present invention relates to container carrying vehicles and, more particularly, to a convertible rail-highway container carrying vehicle which can accommodate a standard ISO (International Standards Organization) tunnel type 40 foot container which is 9'-6" high.
Container carrying railway vehicles are well known and are derived from flat cars of various types with the addition of appropriate hardware to secure the container to the car structure.
Also container carrying highway vehicles such as semitrailer container chassis are widely used for container shipping on highways.
A container mounted on a flat car must be transferred to a highway container chassis in order to reach its final destination, causing delays and extra costs to be incurred. In addition, as the delivery distance increases, all highway transport becomes increasingly uneconomical.
Further, it has been found that high cube containers are more desirable for shipping most commodities and are in high demand by shippers. The largest standard containers which may be legally operated on highways are 9'-6" high and require a tunnel type container configuration. This requires a "gooseneck" chassis design which allows the front of the chassis at the king pin area to nest inside the tunnel recess in the center underfloor of the front of the container.
For economic and service reasons it is desirable to minimize or eliminate costly and time consuming operations employing separate rail and highway container carrying vehicles.
It is also desirable for economic reasons to operate long trains of lightweight construction. However, the structural strength requirements for rail-highway container carrying vehicles must be on the order of 400,000 pounds or more, thus precluding the use of standard type highway designs for container chassis or gooseneck chassis.
Further it has been found that rail-highway container vehicles capable of carrying 9'-6" containers have not been developed which possess the requisite strength to operate in long trains or meet the overall highway height requirement of 13'-6".
It would therefore be desirable to provide a single lightweight vehicle that can be used for both rail and highway operations while carrying maximum height cargo containers without removing the container from the vehicle.